Gasket devices positioned between joined pieces or pipes are used to create a seal between the joined pieces and to prevent leakage of material from the joined pieces at the joint. Moreover, in addition to providing a seal for the joint, in some situations it is also desirable to electrically isolate the joint pieces. One example of corrosion resistance for pipelines is cathodic protection. This type of corrosion protection typically requires sealing joints by providing electrical isolation. Another example is when two sides of the joint are made of different metals in which the electrical potential difference between the two metals can create a galvanic corrosion cell if the two sides are not electrically isolated. In other situations it may also be desirable to maintain a seal for the joint during a fire. Fires are dangerous to pipeline workers but the fires can become even more dangerous and deadly if the seal between joints is not capable of containing the material in the pipes during a fire.
Gasket devices have been developed to effectively do one of sealing, electrical isolation, or fire safety. Therefore, multiple gaskets must be used to combat situations where all of these concerns are present which can lead to increased costs as well as compatibility and size issues. Other problems exist when multiple gaskets are used, for example, one gasket device that effectively seals a joint may melt at high temperatures, such as during a fire, so that the seal between flanges is no longer effective and possibly may leak. Leakage of material such as petroleum or gas can be extremely dangerous and can increase the likelihood of fire. As another example, some materials that are resistive to deformation also conduct electricity. Thus there remains a need for improvement in the field of electrically isolated, fire-safe, effective sealing systems.